This activity is based on an idea from the book
"More Mathematical Curiosities" published by Tarquin - see below
for details.

Follow the instructions below to make your square:

You will need:

Scissors

Clear plastic wallet (A4 or A5 size)

Plain thin card ( or A4 paper)

Ruler

Glue

Squared paper (optional)

Coloured pens or pencils (optional)

What to do:

Cut down the plastic wallet so that it is approximately $15$cm
by $15$cm (keep the edges sealed so that you still have a
pocket).

Now you need to make the numbered pieces. The easiest way to do
this would be to print them out onto thin card or paper. Click here to see our
versions. (Sixes and nines are underlined so that you can tell the
difference between them.)
If you can't print them, copy the numbers onto squared paper. Make
sure you colour the squares as we have (or write the numbers in
colour). It is important that the numbers written upside-down are
upside-down!

Cut out each double number set.

Fold each pair of numbers away from you along the grey line and
stick the backs together. You should end up with sixteen squares
with a number on each side.

Before you try the double-sided puzzle, it is worth having a go
at the magic square on just one side.
You need to arrange the numbers $1-16$ in a $4$ by $4$ grid so
that:

All rows, columns and diagonals add up to $34$.

Each $2$ by $2$ group of the square adds up to $34$.

When you've done that (there are $48$ different ways of doing
it!), you're ready to have a go at the Double-Sided Magic
Square.

Slip the squares inside the plastic wallet so that you can see both
sides.
The challenge now is to make sure both sides of the square obey the
rules above.
The colours of the squares give you a clue to the arrangement:

On one side, all the numbers in the same row are the same
colour. From top to bottom of the square, the rows are red, yellow,
blue then green.

On the other side, all numbers in the same column are the same
colour. From left to right these columns are blue, red, green and
yellow.

To make a 3D version of the square, look at
"More Mathematical Curiosities" published by Tarquin. It is priced
at £4.95 and can be ordered directly from Tarquin
Publications: http://www.tarquinbooks.com

The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the
NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to
embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities
can be found here.